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North American Geology. It’s complicated. I’m pretty sure Amanda and I were abducted by aliens this morning. This is not the first time for me. I was abducted with two others about 20 years ago in Southern Maine while looking for antiques, back when you could still get them cheap even in antique stores (inexpensive antiques, not aliens). You can tell you were abducted because one moment it is a certain time and the next moment is it much later in time and you have no memory whatsoever of he ensuing span of minutes or hours. Since that is essentially impossible, alien abduction is pretty much the best possible explanation.

Back in Maine, it caused us to miss a critical turn just by the Big Red Barn antique store. This morning, it caused Amanda to go rushing out of the house only half ready for a day of teaching Life Science and me to sit here wondering, “Why did I just spend 20 minutes reading pages in this creationist web site called Answers in Genesis?”

Well, I’m not sure how Amanda’s day is going to go, but I’m going to make use of this abduction and talk about the Grand Canyon.

I think the people at Answers in Genesis were also abducted by aliens and replaced with aliens-in-training who have returned to Earth to do some kind of experiment on us, specifically, on how humans reason and come to believe things. At least, that’s the best explanation I have for the crap they put on that site.

I was just reading a piece by Gary Parker from “Chapter 3: The Fossil Evidence,” posted on that site, about the Grand Canyon. Gary claims that the deeper sediments (Precambrian) exposed by the Grand Canyon are exactly the kind of sediment one would expect from very slow-moving water, because it is all “lumpy” and contains “virtually no fossils.” In contrast, the upper layers are the kind you would expect to be deposited very quickly and contain more fossils. The boundary between the two, according to Gary, is the moment of the Noachian flood. So, the entire 1,300 meter or so “layer” above the Precambrian/Noachian boundary was deposited some time during and/or just after the flood itself, which was a forty day (and night) long period of time.

The description Parker provides has the same look and feel as the description of any complex geological section, a description you might read in an exhibit or hear on the little tape machine you borrow to provide a guided tour around a museum. Parker points out things you can see (especially if they are pointed out to you) and then provides explanations that may sound incredible at first (like all the flood waters came from under the ground, from separation of magma from the water the magma contains). This seemingly unbelievable assertion is then matched to a scientific-sounding fact (ask any geologist…most of the water on the earth is actually trapped in the magma beneath the earth’s crust!) that in and of itself also seems rather incredible. But if you present one incredible fact to amaze the audience, then quickly “explain” it by a second equally incredible fact, you’ve got a good story and the listener seems to be having some kind of a learning experience. The learning experience itself feels good, and it feels even better than it otherwise might if it happens to bolster some preexisting preference or belief, like a belief in the literal truth of your most holy sacred text.

Parker is using a formulaic approach to explaining things that historians of science and other scholars know is used in much of the great and famous writing about history, the natural world, morality, and the struggles that life presents. The Greek myths use this approach to bring the reader through various levels of discomfort, fear, loathing, desire, and so on, and then to a state of catharsis. The assertions are provided to the reader or exhibit viewer along with key facts that, in isolation, are odd but might seem unimportant, but which are really key to the overall model. Spectacular events or seemingly outrageous assertions are made, but they are then tied together to make a story that returns a sense of order to the universe. This is all done in the context of seeming normalcy.

The hero (the sense of reason) is challenged, sometimes fails the challenge, sometimes defeats the challenger, cycling through challenge and failure a few times, then in the ideal story, just when it all seems most hopeless, manages to assemble all of the prior failures into a glorious redemption…a new way of thinking. The hero is transformed from a previously unrecognized state of ignorance to a state of new and higher understanding.

This process of storytelling and exhibition is a tried and true way of getting one’s point across, and is exploited by purveyors of both scientific realities and pseudo-scientific self-serving crap (the former being, say, Park Service Exhibit Designers, the latter, creationists).

Let’s examine this model in the context of Parker’s version of the Grand Canyon Myth. In this analysis, the “hero” is not a person but rather a belief held by a person and shared by others. The hero (a belief) arrives on the scene, naive:

I once believed and taught, like so many others, that the rock layers in Grand Canyon represented stages in evolution laid down over vast eons of time.

The hero is challenged and converted from belief to uncertainty, the worst thing that can happen to a “belief”…

Although most people relate the Flood to “forty days and forty nights of rain,” the Bible says that the Flood began when “the fountains of the great deep burst forth.” It seems that most of the water came from below, not from above.

How can this be? The hero is clearly defeated by this assertion. Most people with a rational view of the world, encountering this, would simply allow the hero, the belief, to walk away unscathed because this assertion is so absurd. In other words, you (as the holder of the belief) simply stop playing the game. Whoever is saying this crazy thing is obviously…crazy…and your mind is not changed. You worships your heroes, and in this case, you are not going to admit that the hero (your belief) would be defeated if this fact…”fountains of the great deep” bursting forth, etc….turned out to be true.

If you are a rational person with some training in geology, you do walk away. But if you want to believe in the literal nature of your holy book—your bible—then maybe you stick around for more. So you keep reading.

Few people realize what a tremendous amount of water is found in molten rock (magma) trapped beneath the earth’s surface! When a hole or crack develops in the solid rock capping the more liquid magma, the pressure release causes the super-super hot water to flash into steam, and “BOOM” we have an upward-outward rush of vapor, gas, dust, and ash, producing a volcanic explosion and/or an outpouring of liquid rock on the surface (lava)!

Ah, for those of you who stuck around, the hero is redeemed. The ugliness of the theory, the discord, is erased because it turns out that there is an overwhelmingly cool and inspiring “fact”…stated here in glorious catastrophic terms. The counterintuitive has arrived on the scene to rescue the badly damaged hypothesis, but also to transform it. The difference between the two ways of interpretation are reconciled. Just to make sure, Parker adds a reassurance….

A geologist looking for a way to start a worldwide flood could hardly come up with a better mechanism than breaking up the “fountains of the great deep!”

Well, if that is what a geologist would do, then you can do it too, right?

And the new story is now applied to several other observations and shown to be a consistent, rational model that explains everything the author chooses to test it with. The following bit cements the argument especially for the Libertarian-oriented, the hands-on kinda guy, the people from Missouri (the “show me” state), etc:

When Biblical creationists/Flood geologists offer explanations for the rock layers in Grand Canyon, they appeal neither to Biblical authority (the Bible doesn’t mention Grand Canyon!) nor to mystical or supernatural processes. They appeal, instead, directly to the evidence we can see, touch, and measure. That evidence seems to suggest that processes we do understand, like turbidity currents, explain what we see–except that the evidence also tells us that the scale was regional, continental, or even global, not just local.

The most important, but unstated, characteristic of this argument, without which the argument could not be made, is the closed context. The whole Grand Canyon story told by Parker is based entirely on what is observed within the Grand Canyon itself and virtually nothing else (he links to his model observations of the Mississippi River, but that’s about it for reaching outside the context of this story).

The reasons why his model is utterly wrong are many, but there are two categories of “wrongness” that apply. One is the most obvious but it is not the one that matters. It is, in fact, a trap laid by the creationist Parker, following the strategy of the famous Duane Gish (of the “Gish gallop“). This is the category of what is wrong about the details. For example, the geophysics of getting the water to rush out of the magma and flood the earth. That’s actually a very big part of the model, and it is in violation of much of what we know, but it is also about a process that is hard to explain, hard to understand, and over which scientists and creationists can do battle in a public context and do little more than bore the audience. It is also one of many, many details that are wrong in similar ways with this model.

For this category of wrong things about Parker’s model, Parker wins. It does not matter that everything is wrong if the attempt to falsify each part of the argument does not convince the onlooker, or even interest the onlooker. The onlooker fails to be convinced by the one-by-one refutation of the model because the model itself is beautiful and coherent, and the one-by-one arguments are petty and scrappy. Parker’s creationist model of the Grand Canyon (quote mining opportunity here!) is beautiful and coherent not because it is correct but because it is a good story put together in the classic way of telling stories that influence and enthrall us humans.

The other category of “why this is wrong” is actually a much more beautiful, much more coherent, much cooler, and much more powerful model. It is a very simple, unary fact demonstrated over and over again across the planet by hard working geologists. This is the fact of basin evolution and history. And it is astounding and beautiful.

If you step back from the Grand Canyon and look on a more continental level, you see a story about major subduction, mountain building, plate movement, a really sexy thrust fault or two, and seemingly incredible inland seas, set against a lush background of eons of evolutionary change.

This is the story of the Grand Canyon:

A huge continental region left alone by tectonics for a long period of time erodes flat. Then a huge basin forms. Mountains arise to form the edge of the basin; we see evidence of subduction making the basin deeper. The basin fills with water and undergoes a series of infilling and reflooding events: fresh water, salt water, in-between water. We see the edges of the many incarnations of great sea as ancient beaches. We can find islands. We can demonstrate how it forms a barrier between mini-continents, on which evolution of many lineages proceeds for a time with separate histories, and so on.

The basin fills with sediment. The landscape flattens. Then mountains form again and the basin reforms, deepens again. Shorelines form; the biogeography is again transformed. Then the mountain building and basin formation again wanes, and the continent flattens. Then it all happens again.

It has happened a number of times since the beginning of the Earth.

The story of individual basins is fascinating, because in most cases you can describe the basin formation, filling, flattening, and reforming cycle a few times and then you find yourself at the beginning of the planet’s post-flaming-ball-of-molten-stuff phase. In other words, the basin cycle, which we see repeated again and again in a handful (dozens) of places on the earth is both very large (continental or subcontinental in scale) and very slow.

Describing the Earth in reference to basin cycles would be like describing the history of western civilization through the eyes of members of a family of very long-lived individuals. So, great-grandpa lived through the late Stone Age and the Neolithic; grandpa was born at the time of the Old Kingdom in Egypt and died during the early Roman period. Dad is still alive, and Junior is a babe in arms ready to observe the next few thousand years.

Imagine writing that story. That is the view of the history of the Earth that the basins reflect. The Grand Canyon itself skips some of these generations due to erosion, so the lowest level shows perhaps the first or second cycle of basin evolution, and all the upper layers together show a later cycle. Only by examining localities across the breadth of the continent can we piece together all of the cycles and understand the continental history the way it really happened.

So we see in the Grand Canyon’s geological record tectonic movements and phases of infilling and erosion, but what is different now is that we are here to observe the details of this most recent erosional phase. In some areas, the erosion is broad in nature and we see the formation of badlands. In other areas, the erosion is apace with mountain building, so we see things like the Platte River, bringing huge loads of sediment from the Rockies across the plains. In a couple of areas, large flat parts of the ancient, infilled basin are being cut down by just one or two rivers in a very simple system, so all the erosion is concentrated in one linear formation…so we get very impressive, sometimes “grand” canyons.

The story of the continent seems just as good of a story as the story of the Grand Canyon itself, but it is in fact is better because it leads to a greater, more accurate understanding of Earth history. It does not matter if you provide a visitor to the Grand Canyon with the creationist or the real (geological) story. Both stories are weakened by the lack of context. Both stories leave many loose ends that can only be tied up if we step far enough back to see the very big picture. But by stepping back and contextualizing the Grand Canyon in two ways (as one geological feature among many, and as interpreted by a well-established set of geological principles) one can understand this particular, spectacular gash in the landscape. More importantly, at this global level, the difference between the basin evolution model describing events taking place over hundreds of millions of years and the creationist model describing events taking place over about a month is seen very clearly.

The basin evolution model is correct, the creationist model is wrong.

A: The northern part of this continent has been glaciated and reglaciated numerous times, with the landscape thusly transformed over and over again, during the last two million years.

B: The western part of the continent has experienced several different episodes of mountain building. Continental margins often experience mountain building because mountains form as continents rip apart and they form as continents run into each other or slide past each other.

C: The eastern part of the continent has experienced an entirely different but similar set of mountain building episodes, mainly caused by the repeated closing and opening of the Atlantic Basin.

Notice the big wet spots along the southern part of the North American continent…which we call the Gulf of Mexico and the Caribbean. These are parts of the continent and are currently low-lying basins being filled with sediment washing off the continent.

5 thoughts on “Abducted by Aliens…and Dropped Off at the Grand Canyon”

Then a huge basin forms. Mountains arise to form the edge of the basin; we see evidence of subduction making the basin deeper.

Don’t you mean subsidence, not subduction? Subduction is the sliding of one tectonic plate under another. Subsidence is how basins compress under their own weight, making room at the top for more sediment.